Dave, Since kref_get_unless_zero() was brought in by drm, could we add this to drm-next? Thanks, Thomas On 06/30/2016 12:52 AM, Jason A. Donenfeld wrote: > This was positively reviewed by maintainers but never picked up. Can > someone queue this for 4.7 or 4.8? > > Thanks, > Jason > > On Mon, Feb 1, 2016 at 10:53 PM, Jason A. Donenfeld <Jason@xxxxxxxxx> wrote: >> This was positively reviewed but never picked up. Can someone queue >> this for rc3? >> >> Thanks, >> Jason >> >> On Sun, Oct 11, 2015 at 9:59 PM, Thomas Hellstrom <thellstrom@xxxxxxxxxx> wrote: >>> Reviewed-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx> >>> >>> >>> On 10/10/2015 12:56 PM, Jason A. Donenfeld wrote: >>>> On most platforms, there exists this ifdef: >>>> >>>> #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) >>>> >>>> This makes this patch functionally useless. However, on PPC, there is >>>> actually an explicit definition of atomic_inc_not_zero with its own >>>> assembly that is slightly more optimized than atomic_add_unless. So, >>>> this patch changes kref to use atomic_inc_not_zero instead, for PPC and >>>> any future platforms that might provide an explicit implementation. >>>> >>>> This also puts this usage of kref more in line with a verbatim reading >>>> of the examples in Paul McKenney's paper [1] in the section titled "2.4 >>>> Atomic Counting With Check and Release Memory Barrier", which uses >>>> atomic_inc_not_zero. >>>> >>>> [1] https://urldefense.proofpoint.com/v2/url?u=http-3A__open-2Dstd.org_jtc1_sc22_wg21_docs_papers_2007_n2167.pdf&d=BQIBAg&c=Sqcl0Ez6M0X8aeM67LKIiDJAXVeAw-YihVMNtXt-uEs&r=vpukPkBtpoNQp2IUKuFviOmPNYWVKmen3Jeeu55zmEA&m=z5Nd9sYiJMKiphNjyZp6XT5CbayXMBlcb903f260pDY&s=HEHX3CuXRs2GRRQWuC4Vef6iJMwdilKVRkiZgJpjEpA&e= >>>> >>>> Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> >>>> --- >>>> include/linux/kref.h | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/include/linux/kref.h b/include/linux/kref.h >>>> index 484604d..83d1f94 100644 >>>> --- a/include/linux/kref.h >>>> +++ b/include/linux/kref.h >>>> @@ -166,6 +166,6 @@ static inline int kref_put_mutex(struct kref *kref, >>>> */ >>>> static inline int __must_check kref_get_unless_zero(struct kref *kref) >>>> { >>>> - return atomic_add_unless(&kref->refcount, 1, 0); >>>> + return atomic_inc_not_zero(&kref->refcount); >>>> } >>>> #endif /* _KREF_H_ */ _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
